From an AP story by Isabel Debre headlined “5 things to know about the Hamas militant group’s unprecedented attack on Israel”:

Without warning on Saturday, Gaza’s militant Hamas rulers attacked Israel by air, land and sea. Millions of Israelis in the country’s south awoke to the searing sound of incoming rockets and the inevitable thud of impact. Air raid sirens wailed as far north as Tel Aviv. Israel’s anti-rocket interceptors thundered in Jerusalem.

In an unprecedented escalation, armed Hamas fighters blew up parts of Israel’s highly fortified separation fence and strode into Israeli communities along the Gaza frontier, terrorizing residents and trading fire with Israeli soldiers.